Tetranuclear Copper complexes with new β—diketone and β—iminoketone—containing ligands

Novel tetranuclear copper complexes,Cu4(OH)2(ClO4)3 (HA).H2O(1)and Cu4(ClO4)5(H3B).3H2O(2),were synthesized by reacting 1,5-bis(1‘-phenyl-3‘-methyl-5‘-pyrazolone-4‘)-1,5--pentanedione with 1,3-propanediamine and 2-hydroxyl-1,3-propanediamine in the presence of a template reagent copper ion ,New[2 2] type open cyclic multidentate ligands are also obtained from the reaction(H4A) and H6B stand for new compounds from 1,3-propanediamine and 2-hydroxyl-1,3-propanediamine,respectively),They each contain five C=O ,three C=N and one NH2 group[s,The complexes were characterized by elemental analyses,conductivity,FR-i.r.electronic spectra and extended X-ray absorption fine structure(EXAFS),Copper ions in (1) are basically four coordinate with tetragonal geometry.The average coordination bond distances of Cu-N and Cu-O are 1.91 A and 2.05A .In(2).copper ions are primarily five coordinate with square-based pyramidal geometry.The average coordination bond distances of Cu-N and Cu-O are 1.93 A and 2.08 A.Four copper atoms in molecules may be arranged tetragonally.Both the ligand field and the coordination bonds in complex(1) are stronger than those in(2).Investigations on variable temperature susceptibilities show that some antiferromagnetic exchange interaction exist in the complexes,The plots of x-1 versus T obey the Curie-Weiss law only at low temperature.Preliminary results of a bioassay indicate that the two complexes have some antitumour activity in vitro.     

Preparation and characteristics of ^117mSN—HEDTMP

Tin-117m(t1/2 14d;γ159keV,86%) is an ideal tracer for studying biological behavior of tin compounds as well as for developing clinically-useful radio-pharmaceuticals.It had been reported that Sn-117m[4 ] DTPA has unexpectedly high bone uptake and bone-to-blood ratio,and is potentially useful as an agent for skeletal scintigraphy and radiotherapy of bone tumors.In this work.HEDTMP [N-(2-hydroxyethyl)ethlenediamine-1,1,2-tri(methylene phosphonic acid)] was synthesized.Let it form complex with ^117mSn.The formation conditions,stability and distribution coefficient between oil and water of the complex were investigated.     

Synthesis and biodistribution of [131I]IMPY

The synthesis and biodistribution of β-amyloid plaques imaging agent [^131I]-2- （4′-dimethylaminophenyl）-6-iodoimidazo[1,2-α] pyridine （[^131I]IMPY） were reported. The chemical structure of the labeling precursor 2-（4′-dimethylaminophenyl）-6- （tributylstannyl） imidazo[1, 2-α] pyridine and all its intermediates were verified by IR,HNMR and MS. The radioiodinated compound was prepared using iododestannylation reaction by hydrogen peroxide. Final radiochemical purity was above 95% determined by TLC. The in vivo biodistribution of [^131I]IMPY in normal mice showed excellent brain uptake and washout, indicating this thioflavin-T based small molecular probe has potential for in vivo imaging amyloid deposits.     

N，N,N‘,N’—tetrabutylmalonamide as a new extractant for extraction of nitric acid and uranium（VI）

N,N,N‘,N‘-tetrabutylmalonamide(TBMA) is synthesized and used for extraction of uranyl(Ⅱ） ion from nitric acid media in a diluent composed of 50% 1,2,4-trimethyl benzene (TMB) and 50% kerosene(OK),The effects of nitric acid concentration,extractant concentration,temperature,slating-out agent (LiNO3) and back extraction on distribution coefficients of uranyl(Ⅱ） ion have been studied.The extraction of nitric acid is also studied.The main adduct of TBMA and HNO3 is HNO3.TBMA,and there are more than two kinds of adducts in 3.0mol/L nitric acid solutions,such as HNO3.TBMA,(HNO3)2,TBMA and (NHO3)3.TBMA.The complex formation of uranyl(Ⅱ） ion,nitrate ion and TBMA(1:2:1) as extracted species is further confirmed by IR spectra of the saturated extraction of uranyl(Ⅱ） ion with TBMA,and the values of thermodynamic parameters have also been calculated.     

Extraction of U（VI） and Th（IV） with a novel extractant N,N‘—tetrahexylmalonamide （THMA） in toluene

The dependence of THMA extraction behaviour for U(VI) and Th(IV) on nitric acid concentration,THMA concentratioin and molecular structure of extracted complex has been studied.For nitric acid solutions of 3.0 mol/L a coordinative mechanism may possibly dominate in the extraction of metal catioins,The complex composition of UO2(NO3)2(THMA)2,Th(NO3)4(THMA)2 and Th(NO3)4(THMA03 are proved.     

Inhibition of nicotine-DNA adduct formation by polyphenolic compounds in vitro

Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine], a major alkaloid in tobacco products, has proven to be a potential genotoxic compound. Some polyphenolic compounds can suppress the DNA adduction, and hence act as the potential inhibitors of carcinogenesis. In this study, the inhibitory effects of three polyphenolic compounds, curcumin (diferuloylmethane), resveratrol (trans-3, 5, 4-trihydroxystilbene) and tea polyphenols, on the nicotine-DNA adduction have been investigated in vitro using radiolabelled nicotine and liquid scintillation counting (LSC) technique. Also, the inhibition mechanism of these chemopreventive agents in regard to the activity of the biotransformation enzymes, including cytochrome P450 (CYP450), cytochrome b5 (CYb5) and glutathione S-transferase (GST), has been studied, The results demonstrated that these three polyphenols induced marked dose-dependent decrease in nicotine-DNA adducts as compared with the controls. The elimination rate of adducts reached above 46% at the highest dose for all the three agents with 51.6% for resveratrol. Correspondingly, three polyphenols all suppressed CYP450 and CYb5, whereas curcumin and resveratrol induced GST. We may arrive at a point that the three polyphenols are beneficial to prevent the nicotine adduct formation, and thus may be used to block the potential carcinogenesis induced by nicotine.     

Preparation and preliminary biological evaluation of 99mTc-ANMdU

Technetium-99m-labeled-5-{2-sulfanylethyl-[2-(2-sulfanylethylamino)acetyl]amino}-methyl-2′-deoxy- uridine (99mTc-ANMdU) was reported. The precursor ANMdU was synthesized by six-step reactions and all intermediates were verified with MS and 1HNMR. Using SnCl2 as reducing agent, a labeling reaction was carried out at 100°C for 30 min. The radiochemical purity of the 99mTc-ANMdU was 96.68%. Partition coefficients were 0.92 and 0.70 at pH 7.0 and 7.4 of the phosphate buffer saline, respectively. Biodistribution of 99mTc-ANMdU in normal mice showed that the initial uptake of 99mTc-ANMdU in vivo and the clearance was rapid.     

Shape Coexistence and Band Terminations in ~(131)La

The deformed neutron deficient nuclei in the A=130 mass region have special interesting for their features of smooth band termination and band structures at high spin. The valance space outside the 100Sn or 114Sn core is large enough to produce plenty of interesting band structures. 131La is studied by experiment several years before[1,2]. The recent experimental results of 131La are populated by using the 100Mo(36S, p4n) reaction at beam energy of 160 MeV. Gamma rays from this reaction are detected in the EUROBALL IV array[3]. The highest spin state of the band in [3]La is extended up to 75 /2h for parity and signature ( π ,α )=( ,-1/2). The configuration dependent cranked Nilsson Strutinsky model[4]     

The synergic extraction of uranium（VI） with tri－n－butyl phosphate（TBP） and petroleum sulfoxides（POSO）／benzene

The Synergistic extraction of uranium(VI) from nitric acid aqueous solution with a mixture of tri-n-butyl phosphate(TBP) and petroleum sulfoxides(PSO) in benzene was studied.It has been found that the maximum synergistic extraction effect occurs where the molar ratio of PSO to TBP is one to two.The composition of the complex of synergistic extraction is UO2(NO3)2.TBP.PSO.The formation constant of the complex KTP=57.44.     

Extraction of Th（IV） from nitric acid with 40—benzoyl—2,4—dihydro—5—methyl—2—phenyl—3H—pyrazol—3—thione

The BMPPT(4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione)was synthesized from BMPP.Its m.p.is 106-108℃,The results of the element analysis are as follows:C,68.51%,H,4.51%,N,9.26%,S.11.47%,which are in conformity with the theoretical value(C,69.15%,H,4.76%,N.9.52%,S.10.90%),The solvent extraction of Th^4 from nitric acid solution by BMPPT in benzene was studied.The extraction ability of BMPPT is not so high as that of its parent (BMPP).The Th^4 distribution ratio(DTh)in creases with the increasing pH of the aqueous phase,and pH1/2 for Th^4 was 3.2([BMPPT]=0.10mol/L),When the pH increases,the distribution ratio of Th^4 increasdes linearly with the slope of 1.59,When the concentration of BMPPT increases,the distribution ratio of Th^4 increases rapidly.The lgDTh-lg[BMPPT]is linear with the slope of 1.42 and the extraction mechanism is the cation ion-exchange.     

RADIOBROMINE LABELLING OF 3,4-DIHYDROXY-PHENYL-L-ALANINE AND DISTRIBUTION STUDY IN MOUSE BRAIN

The synthesis of 3, 4-dihydroxy- 6- bromo- phenyl- L- alanine (6- Br- L- dopa ), preparation of 3,4-dihydroxy-6-[ Br] bromo-phenyl-L-alanine(6-77 Br-bromo-L-dopa) and its distribution study in mouse brain are described. The radiochemical yield and radiochemical purity of 6- Br-bromo-L-dopa were 8.5 % and 93 %, respectively. Its distribution in mouse brain after one hour injection indicates that it does pass blood brain barrier. The ratio of uptake in striatum to that in cerebellum was 2.45±0.12. The results appeared that 6- Br-bromo-L-dopa could be used as brain tracer for visualizing dopamine-containing brain structures by using single photon tomography.     

Influence of solvents on extraction of U（VI） by N,N‘—didecanoylpiperazine

Extraction behavior of N,N‘-didecanoylpiperazine(DDPEZ)for U(VI) in a series of solvents from aqueous nitric acid media was investigated for the first time.The dependence of distribution ratios on the concentration of aqueous nitric acid,extractant and temperature has been discussed.The increasing sequence of extractive ability of DDPEZ is given:chloroform,carbon tetrachloride,dimethylbenzene,toluene,benzene.     

Characteristics of Atmospheric Pressure Rotating Gliding Arc Plasmas

In this work,a novel direct current (DC) atmospheric pressure rotating gliding arc (RGA) plasma reactor has been developed for plasma-assisted chemical reactions.The influence of the gas composition and the gas flow rate on the arc dynamic behaviour and the formation of reactive species in the N2 and air gliding arc plasmas has been investigated by means of electrical signals,high speed photography,and optical emission spectroscopic diagnostics.Compared to conventional gliding arc reactors with knife-shaped electrodes which generally require a high flow rate (e.g.,10-20 L/min) to maintain a long arc length and reasonable plasma discharge zone,in this RGA system,a lower gas flow rate (e.g.,2 L/min) can also generate a larger effective plasma reaction zone with a longer arc length for chemical reactions.Two different motion patterns can be clearly observed in the N2 and air RGA plasmas.The time-resolved arc voltage signals show that three different arc dynamic modes,the arc restrike mode,takeover mode,and combined modes,can be clearly identified in the RGA plasmas.The occurrence of different motion and arc dynamic modes is strongly dependent on the composition of the working gas and gas flow rate.     

Preparation and biodistribution of 186,188Re—HEDP for bone tumor therapy

Radionuclides^186,188Re,suitable for tumor therapy and with high specific activity,are prepared through irradiating natural metallic rhenium,instead of costly enriched target,Complexation of rhenium with HEDP(1-hydroxy ethylidene diphosphonate)is mainly dependent on pH values and the reductant concentrations in the medium,and the yield is not less than 0.95 in pH2.0-4.0 and SnⅡconcentration of 0.012-0.018mol/L.The 186,188ReHEDP complex has high stability in vitro and in vivo in the presence of protecting agent,and gives superior biological properties in small animals,similar to those of ^153Sm-EDTMP including faster blood clearance,lower soft tissue residue and higher skeletal uptake with the peak of 0.2576 ID/g at 1h post injection(overseas report 0.0101 ID/g)comparable to that of 153m-EDTMP(0.2644ID/g) at 3h post injection.     

Synthesis of 2-[~(18)F]fluoro-3-[2(S)-2-azetidinylmethoxy]pyridine as a radioligand for imaging nicotinic acetylcholine receptors

Nicotinic acetylcholine receptors (nChRs) are involved in the various pharmacological effects or disease states. In order to study the central nChRs by PET or SPECT, some radioligands have been investigated. In this paper, the procedure for synthesis of 2-[18F]fluoro-3-[2(S)-2-azetidinylmethoxy]pyridine (2-[18F]-A-85380), a potential PET ligand for in vivo imaging nicotinic acetylcholine receptor was described. 2-[18F]-A-85380 was prepared from the precursor, 2-nitro-3-[(1-(tert-butoxycarbonyl)-2-(S)-azetidinyl)methoxy]pyridine(4), which was synthesized with commercial (S)-2-azetid- inecarboxylic acid as starting material. The whole procedure for radiosynthesis and purification was executed in about 1h and 45-55% of the added fluorine-18 was found in the purified 2-[18F]-A-85380, with specific activity of 1.0-2.2×1011 Bq/μmol.     

Sheath Characteristic in ECR Plasma Nitriding

1. IntroductionThe plasma sheath is an important and complexregion for nearly all plasma applications in materials processing. The theoretical and experimental research on the features of sheath is important for making the processing mechanism clear and for selectingthe best processing conditions.The main process Of plasma nitriding has been noal.widely accepted as being dominated b3' the excitednitrogen molecules, ions= and nitrogen atoms [l-41.As to their formation, Aloll [5] thought that i…     

Solvent extraction of uranium（VI） and thorium（IV） in nitric acid solution by N,N,N‘,N’—tetrabutyladipicamide

N,N,N‘N‘-tetrabutyladipicamide(TBAA) has been synthesized,and applied to the extraction of U(VI) and Th(IV) from nitric acid solutions in a diluent composed of 0.50 volume fraction 1,2,4-trimethyl benzene (TMA) and 0.50 volume fraction kerosene(OK),The effects of the aueous nitric acid concentration,extractant concentration,slating-out agent (LiNO3) and temperature on extraction ability of TBAA for U(VI) and Th(IV) have been studied.Back Extraction of U(VI) and Th (IV) from organic phases were performed by dilute nitric acid.The compositions of extracted complexes,equilibrium constants and enthalpies of extraction reactions have also been estimated.The IR spectra of extraction of U(VI) and Th(IV) have been studied.     

Performance of multigap resistive plate chamber in a γ-ray aging test

1 Introduction MRPC is a new type of gas detector [1, 2] devel- oped in the last few decades. It has been proposed to be a substitute for the Time of Flight (TOF) detector used in conventional technology in high-energy nu- clear and particle experiments because of its properties of excellent time resolution, high efficiency, simple structure, insensitivity to magnets, and low energy dissipation. The MRPC technology has been adopted for TOF by the STAR group at Relativistic Heavy Ion C…     

Experiment and Operation of a LHCD—35kV／2.8MW／1000s High—Voltage Power Supply on HT—7 Tokamak

A-35kV/2.8MW/1000s high-voltage power supply(HVPS) for HT-7 superconducting tokamak has been built successfully.The HVPS is scheduled to run on a 2.45 GHz/1MW lower hybrid current drive(LHCD)^[1] system of HT-7 superoonducting tokamak before the set-up of HT-7 superconducting tokamak in 2003.The HVPS has a series of advantages such as good steady and dynamic response,logical computer program controlling the HVPS without and fault,operationa panel and experimental board for data acquisition.which both are grounded distinctively in a normative way to protec the main body of HVPS along with its attached equipments from dangers.Electric power cables and other control cables are disposed reasonably,to prevent singals from magnetic interference and ensure the precision of signal transfer.This paper involves the experiment and operation of a 35kV/2.8 MW/1000s HVPS^[2] for 2.45 GHz/1 MW LHCD system.The reliability and feasibility of the HVPS has been demonstrated in comparison with experimental results of original design and simulation data.     

Time-resolved measurements of NO2 concentration in pulsed discharges by high-sensitivity cavity ring-down spectroscopy

To describe the complex kinetics of formation and destruction mechanism of nitrogen dioxide(NO_2), there is an increasing demand for real-time and in situ analysis of NO_2 in the discharge region. Pulsed cavity ring-down spectroscopy(CRDS) provides an excellent diagnostic approach. In the present paper, CRDS has been applied in situ for time evolution measurement of NO_2 concentration which is rarely investigated in gas discharges. In pulsed direct current discharge of NO_2/Ar mixture at a pressure of 500 Pa, a peak voltage of -1300 V and a frequency of 30 Hz, for higher initial NO_2 concentration(3.05?×?10~(14)cm~(-3), 8.88?×?10~(13)cm~(-3)),the NO_2 concentration sharply decreases at the beginning of the discharge afterglow and then becomes almost constant, and the pace of decline increases with pulse duration; however, for lower initial NO_2 concentration of 1.69?×?10~(13)cm~(-3), the NO_2 concentration also decreases at the beginning of the discharge afterglow for 200 ns and 1 μs pulse durations, while it slightly increases and then declines for 2 μs pulse duration. Thus, the removal of low-level NO_2 could not be promoted by a higher mean energy input.